The much anticipated Gmail feature you have been waiting for is here. Gmail now supports voice and video chat from within the browser. This feature is available now to all the users worldwide. Using this feature, you can voice and video chat for free in the Gmail’s chat window.
To enable the feature, go to http://www.gmail.com/videochat and click on the “Install” button. The plugin will be installed and will ask you to restart your browser (In case your browser is not restarted automatically, you should do it manually). Login to Gmail and open a chat window with the person you want to have voice or video chat with. you will see there is a “Video & more” button instead of the regular “Options” button. Click on the new button and select “Start video chat” or “Start voice chat”. You can switch to a full screen view or pop out the chat window and change the size and positioning as you wish.
In case you do not have a webcam, you can still have voice conversations alongside your email and regular chat. You can click the “pop-out” icon 
to make the video larger, or click the fullscreen icon 
in the upper left-hand corner for a fully immersive experience.
Take a look at this short video to see more:
Thinking about buying a webcam? There are some models available at discount here: http://www.google.com/mail/help/videochat/learnmore.html
